NKP S2 From United States of America, joined Dec 1999, 1714 posts, RR: 6 Reply 1, posted (8 years 9 months 1 week 6 days 17 hours ago) and read 1846 times:
I don't think it's the preservative, which makes a bluish oily-ish smoke.
If it was my guess: I'd say they wet-motored either a new engine, or after an MEC R&R on the existing engine and they didn't quite blow the tailpipe clean of fuel via dry-motor(s).
Corey07850 From United States of America, joined Feb 2004, 2519 posts, RR: 5 Reply 2, posted (8 years 9 months 1 week 6 days 13 hours ago) and read 1691 times:
Here's a video and description I posted a while ago that describes what's going on: